Vision loss, sometimes leading to complete blindness, is a common complication of some forms of advanced diabetes. It is very desirable to find early warning signs of retinal degradation. Determination of the time course of retinal atrophy is important, both for diagnosis and determination of efficacy of treatment. Specifically, we wish to quantify the degree of retinal atrophy or macular degeneration in selected diabetic and control patient populations. This is to be performed by processing photographic data taken from transparencies of fluorescein images of the retina, taken through a Zeiss Fundus camera. This project is designed to determine areas of atrophy on photographic slides of human retinas, to digitize their boundaries, and to process the data to find quantitative trends, using microcomputer hardware and software.